Daimler Freightliner Cascadia 2021, Руководство пользователя

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ECAS Automatic Load Transfer
(ECAS only)
On vehicles equipped with Electronically Controlled
Air Suspension (ECAS), ECAS works in conjunction
with ABS. When wheel slippage is detected by the
ABS, the ECAS system transfers weight from the tag
axle to the drive axle by changing air pressures in
the suspension air bellows, increasing drive wheel
traction.
The ECAS load transfer feature is optimized to apply
the maximum available vehicle load on the drive
axle, up to the maximum allowable limit, determined
by the gross axle weight rating (GAWR). In bobtail or
with a loaded trailer less than the GAWR, the tag
axle supports a negligible load while the drive axle
supports nearly the full weight. Above the GAWR, the
drive axle is loaded with approximately the maximum
allowable load and the tag supports the remainder.
On vehicles equipped with the ICUC, when load
transfer mode is active, "Load Transfer" will display
in the message field of the driver display. See
Figure
15.4 .
Load transfer mode will automatically deactivate
when the vehicle reaches 45 mph (72 kmh).
Engine Brake
Each engine manufacturer uses a specific engine
brake for their engine. Regardless of the manufac-
turer, the engine brake is operated with the principles
outlined in here. Refer to the engine manufacturer’s
operation manual for details of their particular engine
brake product.
WARNING
To avoid injury from loss of vehicle control, do
not activate the engine brake system under the
following conditions:
•
on wet or slippery pavement, unless the
vehicle is equipped with antilock braking
system (ABS) and you have had prior expe-
rience driving under these conditions;
•
when driving without a trailer or pulling an
empty trailer;
•
if the tractor drive wheels begin to lock, or
there is fishtail motion after the engine
brake is activated.
NOTE: When the engine brake is enabled, the
engine brake lamp illuminates in the ICU. See
Table 15.1 .
Whenever vehicle braking is required on good road
conditions, the engine brake may be used in con-
junction with the service brakes. There is no time
limit for operation of the engine brake. However, an
engine brake does not provide the precise control of,
and is not a substitute for, service brakes.
WARNING
Usage of the engine brake as the primary braking
system can cause unpredictable stopping dis-
tances, that could result in personal injury or
property damage. Service brakes are the primary
vehicle braking system.
Since the engine brake is most effective at rated en-
gine speed, gear selection is very important. Gearing
down the vehicle within the limits of the rated engine
speed makes the engine brake more effective. Rec-
ommended engine braking speed is above 1800 rpm
and below the rated speed.
"Control speed" is the speed at which the engine
brake performs 100 percent of the required downhill
braking, resulting in a constant speed of descent.
The control speed varies, depending on vehicle
weight and the downhill grade.
For faster descent, select a higher gear than that
used for control speed. Service brakes must then be
used intermittently to prevent engine overspeed and
to maintain desired vehicle speed.
For slower descent, select a lower gear, being care-
ful not to overspeed the engine. Occasional deactiva-
tion of the engine brake may be necessary to main-
tain the designated road speed under these
conditions.
11/09/2016 f611472
Fig. 15.4, Load Transfer Notification, ICUC
Brake Systems
15.6